Normal female leucorrhea is generally milky white. With the change of menstrual cycle, it presents different characters, sometimes transparent, sometimes sticky and sometimes clear. Generally, there is no abnormal smell and no vulvar itching. If there is abnormal leucorrhea color, such as yellow, green or purulent leucorrhea, it is a manifestation of inflammation. If accompanied by clinical symptoms, such as vulvar itching, or manifestations of urethral inflammation, such as frequent urination, dysuria and other urethral irritation symptoms, it may be caused by vulvar and vaginal inflammation. If abnormal leucorrhea is characterized by bloodshot leucorrhea, cervical lesions and endometrial lesions should be excluded, cervical cancer screening and vaginal ultrasound should be done to determine whether it is caused by other reasons.